Abstract: An amplifier device and a duplexer circuit are provided. The amplifier device includes a first differential amplifier circuit and a controller. The first differential amplifier circuit includes first and second radio frequency (RF) input terminals, first and second transistors, first and second adjustable capacitor circuits, and first and second RF output terminals. The controller adjusts capacitance values of the first adjustable capacitor circuit of the first differential amplifier circuit and the second adjustable capacitor circuit of the first differential amplifier circuit according to at least one of a characteristic related to a first RF input signal of the first differential amplifier circuit, a characteristic related to the second RF input signal of the first differential amplifier circuit, a matching deviation between the first transistor and the second transistor of the first differential amplifier circuit, and a characteristic of the amplifier device.

Abstract: An amplifier device and a duplexer circuit are provided. The amplifier device includes a first differential amplifier circuit and a controller. The first differential amplifier circuit includes first and second radio frequency (RF) input terminals, first and second transistors, first and second adjustable capacitor circuits, and first and second RF output terminals. The controller adjusts capacitance values of the first adjustable capacitor circuit of the first differential amplifier circuit and the second adjustable capacitor circuit of the first differential amplifier circuit according to at least one of a characteristic related to a first RF input signal of the first differential amplifier circuit, a characteristic related to the second RF input signal of the first differential amplifier circuit, a matching deviation between the first transistor and the second transistor of the first differential amplifier circuit, and a characteristic of the amplifier device.

Abstract: A technique for enhancing the frequency tuning range for monolithic RF source generation using fully-integrated coupled Voltage-Controlled-Oscillator (VCO) arrays that contain an odd number of VCOs. Fully-monolithic SiGe VCO arrays using on-chip inductor and varactor with on-chip bias current sources have been carefully designed and simulated in IBM 7HP 0.18 ?m BiCMOS technology and taped out for fabrication. The SPICE simulated frequency and phase tuning of the 1-D VCO×5 array is dependent on the edge VCOs termination impedance, the tuning voltages, and the VCO coupling strength. The simulated data suggests that the enhanced tuning range and beam steering can be accomplished using coupled-VCO arrays without needing complex and bulky phase shifters. This design technique imposes no apparent phase noise penalty but can provide simulated RF frequency tuning range of ˜40% and also ˜+/?25° beam steering for active antennas applications.